Method and composition for the



Reiuued Jan. 9, 1951 METHOD AND COMPOSITION FOR THE TREATMENT OF AIR GuyS. Paschal, Sarasota, Fla., assignor, by mesne assignments, to Airkem,Inc., New York, N. Y.,

a corporation of New York No Drawing. Original No. 2,326,672, datedAugust 10, 1943, Serial No. 378,375, February 11,

1941. Serial N0. 548,781

7 Claims.

reissue specification;

This invention relates generally to a treatment for improving thecondition of the air in a confined space such as a room or chamber. Morespecifically it relates to a substance employed in such treatment and tothe manner of its production.

The treatment in accordance with my invention involves the employment ofchlorophyll. This term "chlorophyll" as herein used is not to beinterpreted in such technical or limited sense as to exclude agents orcompositions of matter which are chlorophyll in modified form orchlorophyll in combination and in which the chlorophyll is so associatedas to be free to function for the attainment of the objects of myinvention.

Chlorophyll functions in the physiology of plant life in effecting, bycatalysis, the conversion of carbon dioxide and water intocarbohydrates. My invention is not concerned with this transformationbut with another use of this substance.

I have discovered that chlorophyll dispersed in air imparts thereto astimulating invigorating quality that resembles fresh country air in itseffect on people breath ng it, to give a sense of well-being even wherethe confined air has become vitiated, as where people are in a roomwithout sufficient ventilation.

It is one of the objects of my invention to refresh the atmosphere in aconfined space. This object I attain by dispersing chlorophyll in suchan atmosphere.

[I have further discovered that, where I employ chlorophyll in thismanner for refreshing the atmosphere of a confined chamber. therapeuticconditions such as colds are beneficially affected or even prevented,apparently because of some physiological effect which the chlorophyllhas upon the mucous membrane of the respiratory passage. It is mythought that these beneficial therapeutic effects are due to a catalyticaction parallel to what occurs in plants, and which makes possible orhastens certain chemical reactions in the exposed mucous membrane or inthe associated tissues] While I have discussed the freshening effect ofchlorophyll on air as an action on the air itself, it is of coursepossible that the effect is a subjective one, resulting from the actionof the chlorophyll in the air on the tissues of t e human body ratherthan on the air, and that the treatment of air which is breathed maytherefore be described as an indirect treatment of mucous membrane.

I have found that the handling of chlorophyll for the purposes ofattaining my invention presents the dimculty that it is relativelyinactive Application for reissue August 9, 1944,

(Cl. 21-53) Matter enclosed in heavy brackets If appears in the originalpatent -but forms no part of this matter printed in italics indicatesthe additions made by reissue this object I attain by associatingformaldehyde with chlorophyll because I have discovered thatformaldehyde has the peculiar characteristic that when combined withchlorophyll it permits the chlorophyll to be used more efllciently andeffectively for the attainment of my invention.

While chlorophyll serves as an atmospheric refreshant, it does notappear to have any germicidal effect nor does it appear to affect atmosepheric odors. Formaldehyde, on the other hand, has a germicidal effectand does counteract and destroy odors, but is itself an irritant and adepressant, and has a characteristic odor of its own which isdisagreeable to many people. Its action in counteracting and destroyingatmospheric odors is apparently a chemical reaction with odor substancesin the vapor phase, which results in a decrease in the odor intensity,dependent upon the amount of formaldehyde used. until a neutral point isreached at which the atmospheric odors have been entirely removed. Anyincrease in the amount of formaldehyde beyond this point will increasethe formaldehyde atmosphere, and again create an undesirable condition.While formaldehyde possesses this odor-destroying property, I have foundthat at the neutral point mentioned hereinabove, the air, whileodorless, is flat, or vitiated, that is to say, it lacks thecharacterist c of freshness which is associated with country or seashoreair. This lack of freshness is su plied by the chlorophyll in accordancewith my invention and in this manner a further object of mv invention isattained.

While, for the reasons stated, th association with chlorophyll offormaldehyde is highly desirable, because of the advantages that resultfrom that association, it is to be understood that the broader purposesof my invention can be effected by the use of the chlorophyll withoutits being associated with formaldehyde as, for example, where thebenefits of that association are either not required or desired.

A wide field of use for my invention is in the air conditioningindustry. The air delivered by air conditioning systems has a peculiarstale character of its own, which may be due to odors of "belowthreshold value. that is, odors of such low intensity that they give nopositive odor impression. Even at such low intensity they may act asdepressants, which treatment of the air according to my invention maycounteract.

eases The odors found in thesev systems, whether noticeable or belowthreshold value" have been found to be due partly to bacteria and moldwhich, in the absence of natural light, develop in deposits of air-bornesolids on coils, filters, duct walls, drip pans and drains, and whichcause putreiaction resulting in a dank odor. Another source of theseodors is the absorption, by dust collecting on filters and duct walls,of odors carried through the system by recirculated air and given onagain by said dust. A third cause of odor is that contributed byinsulating materials, adhesives, viscous filter material, andparticularly corroding metallic surfaces.

The cumulative effect of these odors, even where it is below thresholdvalue, is suflicient to impart a character to the air that isdepressive.

By the treatment of air in such a system in accordance with my inventionthis condition is corrected by its sterilizing action, [which destroysgerms and odors in the system, as well as disease germs, such as thosecausing colds, which may be carried into the system and contribute tothe spreading of disease by recirculating them,] and further by theintroduction of a freshening agent into the system.

I will here give the steps I employ in arriving at an association ofchlorophyll and formaldehyde whereby the objectives of my invention areattained. For a solution in a gallon of solvent, I mix three ounces ofchlorophyll into a one gallon solution of water and ethyl alcohol, themixture being stirred slightly. Sixteen ounces of commercialformaldehyde are added slowly, the solvent being agitated violentlywhile being maintained at a temperature of 80 to 85 F. Commercialformaldehyde is generally a 40% solution in water. The solution thusarrived at is intended for treatment of the air of a confined space andits dispersion is effected for example, by spraying from a closedcontainer or by evaporation from an open container. Accordingly theprocess for jreshening air comprises dispersing from chlorophyll, asolution containing chlorophyll or a solution containing formaldehydeand chlorophyll, into the air, an emission having the capacity and insuch amount as to cause jreshening of the air.

The disclosure that has just preceded setting forth the details of amanner for associating the ingredients will be understood to be merelyfor exempliflcation and therefore not in a limitative sense unlessotherwise expressly specified by the language of the claims.

Having thus described my invention and illustrated its use, what I claimas new and desire to secure by Letters Patent is:

[1. The process of treating the air in a confined space to freshen itthat comprises the step of causing chlorophyll to be diffused into saidspace] g [2. The process of treating the air in a confined space tofreshen it that comprises the step of causing a solution of chlorophylland formaldehyde to be'difl'used into said space] 3. The process oftreating the air in a confined space that comprises the step ofdispersing into said space, a solution containing chlorophyll andformaldehyde in the proportions quantitatively of approximately 3 of theformer to 16 of the latter in 40% commercial solution.

4. The process of treating the air in a confined space to freshen itthat comprises the step of causing a solution of chlorophyll to bediffused into said space by spraying the solution into said space.

[5. The treatment of air circulating in an air conditioning system whichcomprises the steps of causing diffusion into said circulated air of amixture of chlorophyll and formaldehyde] 6. The treatment of aircirculating in an air conditioning system which comprises the steps ofcausing diffusion into said circulated air of a mixture of chlorophylland formaldehyde by spraying said mixture into the air,

[7. For use in an air conditioning system a circulating mediumconstituted by air having dispersed therein a mixture of chlorophyll andformaldehyde] 8. An air freshing composition for use in the treatment ofair in a confined space comprising chlorophyll and formaldehyde insolution [for diffusion in said space].

9. An air Ireshing composition for use in the treatment of air in aconfined space comprising a chlorophyll and formaldehyde composition.

10. The process for freshing air in a confined space that comprisesdispersing chlorophyll into the air in said space by spraying.

11. The process for freshenmg air in a.- confined space which comprisesdispersing chlorophyll into the air in said space in such an amount asto cause lreshening of the air in said space.

GUY S. PASCHAL.

REFERENCES CITED The following references are of record in the OTHERREFERENCES Moure, La Presse Medicale, July 24, 1935, pages 1172-1174.

Pauling, Chemical and Engineering News, October 13, 1947, page 2970.

Briggs, "Summary and Conclusions from Report on the Products Sold underthe Trade Names Air-Wick" and "Airkem." Joint Report from the NationalBureau of Standards and the National institute of Health to the FederalTrade Commission, Washington, D. C., May 5, 1944, 5 pages.

Consolazio et al., Heating, Piping and Air Conditioning, March 1947.American Society of Heating and Ventilating Engineers Journal Section,pages 103-117.

De Navarre, American Perfumer and Essential Oil Review, May 1944, page31.

DiGiorgio, Chemical and Engineering News, page 3322, November 10, 1947.

Wilkstatter et al., Investigations on Chlorophyll, Translation by Shertzet al., 1913, page 68.

Bennett, H., The Chemical Formulary, volume III, page 105 (1936), andVol. 1, page 149 (1933) published by D. Van Nostrand, N. Y.

Pharmacopoeia by Martindale and Wescott Vol. 1, 20th Ed. l932pp. 122 to127.

